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Forest Ecosystems 2023年第3期10卷 316-327页

作者： Ewa Błońska wojciech Prazuch Jarosław Lasota Department of Ecology and Silviculture Faculty of ForestryUniversity of Agriculture in Krakow29 Listopada 46 Str.31-425KrakowPoland

The main objective of our study has been to determine the role of deadwood in the shaping of the amount of soil organic matter fractions in mountain forest *** this purpose,a climosequence approach comprising north(N)and south(S)exposure along the altitudinal gradient(600,800,1000 and 1200 m a.s.l.)was set *** comparing the properties of decomposing deadwood and those of the soils located directly beneath the decaying wood we drew conclusions about the role of deadwood in the shaping of soil organic matter fractions and soil carbon storage in different climate *** basic properties,enzymatic activity and fractions of soil organic matter(SOM)were determined in deadwood and affected directly by the components released from decaying *** decomposed deadwood impacts soil organic matter stabilization more strongly than the less decayed deadwood and the light fraction of SOM is more sensitive to deadwood effects than the heavy fraction regardless of the location in the altitude *** in SOM mineral-associated fraction C content is more pronounced in soils under the influence of deadwood located in lower locations of warmer *** released from decaying wood stimulate the enzymatic activity of soils that are within the range of deadwood influence.

关键词： Enzyme activity Forest soils Heavy fraction Light fraction Soil organic matter

High-resolution,three-dimensional magnetic resonance imaging axial load dynamic study improves diagnostics of the lumbar spine in clinical practice

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World Journal of Orthopedics 2022年第1期13卷 87-101页

作者： Tomasz Lorenc Marek Gołębiowski wojciech Michalski wojciech Glinkowski I^(st)Department of Clinical Radiology Medical University of WarsawWarsaw 02-004Poland Department of Mathematical Oncology Maria Skłodowska-Curie National Research Institute of OncologyWarsaw 02-781Poland Center of Excellence“TeleOrto”for Telediagnostics and Treatment of Disorders and Injuries of the Locomotor System Department of Medical Informatics and TelemedicineMedical University of WarsawWarsaw 00-581Poland

BACKGROUND The response to axial physiological pressure due to load transfer to the lumbar spine structures is among the various back pain *** the spine adaptation to cumulative compressive forces can influence the choice of personalized treatment *** To analyze the impact of axial load on the spinal canal’s size,intervertebral foramina,ligamenta flava and lumbosacral *** We assessed 90 patients using three-dimensional isotropic magnetic resonance imaging acquisition in a supine position with or without applying an axial compression *** structures were measured in the lumbosacral region from L1 to S1 in lying and axially-loaded magnetic resonance images.A paired t test atα=0.05 was used to calculate the observed *** After axial loading,the dural sac area decreased significantly,by 5.2%on average(4.1%,6.2%,P<0.001).The intervertebral foramina decreased by 3.4%(2.7%,4.1%,P<0.001),except for *** flava increased by 3.8%(2.5%,5.2%,P<0.001),and the lumbosacral angle *** Axial load exacerbates the narrowing of the spinal canal and intervertebral foramina from L1-L2 to *** compressive forces thicken ligamenta flava and exaggerate lumbar lordosis.

关键词： Lumbar spine Low back pain Musculoskeletal disorder Diagnosis Axial loading Magnetic resonance imaging Spine biomechanics

Optical properties of silica sol-gel materials singly- and doubly-doped with Eu^3＋and Gd^3＋ ions

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Journal of Rare Earths 2016年第8期34卷 786-795页

作者： Natalia Pawlik Barbara Szpikowska-Sroka Marta Soltys wojciech A. Pisarski Institute of Chemistry University of Silesia 9 Szkolna Street 40-007 Katowice Poland

In present work, the optical and structural properties of silica sol-gel glasses and glass-ceramic materials singly- and dou- bly-doped with Eu3＋ and Gd3＋ ions were investigated. The optical properties of studied systems were determined based on absorption, excitation and emission spectra as well as luminescence decay analysis. Conducted studies clearly indicated a significant enhance- ment of visible emission originated from Eu3＋ ions as a result of changing the excitation mechanism, via Gd3＋Eu3＋ energy transfer. The luminescence intensity R-ratio was analyzed before and after heat-treatment process upon excitation at λex=393 nm and λex=273 nm. Moreover, the influence of excitation wavelength on luminescence decay time of the 5D0 excited state was also analyzed. The GdS＋-Eu3＋ energy transfer efficiencies for precursor and annealed samples were calculated based on luminescence lifetime of the 6p7/2 level of Gd3＋ ions. The X-ray diffraction measurements were conducted to verify the nature of obtained sol-gel materials. In re- sult, the formation of orthorhombic GdF3 nanocrystal phase dispersed in amorphous silica glass host was identified after annealing. Obtained results clearly indicated an incorporation of Eu3＋ activators into formed GdF3 nanocrystals. Thus, conducted heat-treatment process led to considerable changes in surrounding environment around Eu3＋ ions. Actually, it was found that en- ergy transfer phenomenon and heat-treatment process were responsible for significant improvement of Eu3＋ luminescence in stud- ied sol-gel samples.

关键词： nanocrystals sol-gel method luminescence rare earths

Acute ulcerative jejunal diverticulitis:Case report of an uncommon entity

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World Journal of Gastroenterology 2008年第40期14卷 6265-6267页

作者： wojciech Staszewicz Michel Christodoulou Stefania Proietti Nicolas Demartines Service de Chirurgie Viscerale Centre Hospitalier Universitaire Vaudois Service de Radiologie Centre Hospitalier Universitaire Vaudois

Jejunal diverticulosis is a rare entity with variable clinical and anatomical *** reported incidence varies from 0.05% to 6%.Although there is no consensus on the management of asymptomatic jejunal diverticular disease,some complications are potentially life threatening and require early surgical *** report a case of an 88-year-old man investigated for acute abdominal pain with a high biological inflammatory *** of multiple giant jejunal diverticulum was discovered at abdominal computed tomography (CT).As a result of the clinical and biological signs of early peritonitis,an emergency surgical exploration was *** first jejunal loop showed clear signs of jejunal *** segmental jejunum resection with end-to-end anastomosis was *** report confirmed an ulcerative jejunal diverticulitis with imminent perforation and acute local *** patient made an excellent rapid postoperative *** diverticulum is rare but may cause serious *** should be considered a possible etiology of acute abdomen,especially in elderly patients with unusual *** CT is the diagnostic tool of *** best treatment is emergency surgical management.

关键词： Jejunal diverticulum Diverticulitis Surgery Tomography

Non-viral causes of hepatocellular carcinoma

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World Journal of Gastroenterology 2010年第29期16卷 3603-3615页

作者： wojciech Blonski David S Kotlyar Kimberly A Forde Division of Gastroenterology University of Pennsylvania Department of Gastroenterology Medical University Wroclaw Department of Internal Medicine Montefi ore Medical CenterAlbert Einstein College of Medicine

Hepatocellular carcinoma(HCC) is the most common primary liver malignancy and represents an international public health concern as one of the most deadly cancers *** main etiology of HCC is chronic infection with hepatitis B and hepatitis C ***,there are other important factors that contribute to the international burden of *** these are obesity,diabetes,non-alcoholic steatohepatitis and dietary *** evidence suggests that the etiology of many cases of HCC is in fact multifactorial,encompassing infectious etiologies,comorbid conditions and environmental *** of relevant non-viral causes of HCC will aid in preventative efforts to curb the rising incidence of this disease.

关键词： Hepatocellular carcinoma Etiology Nonalcoholic steatohepatitis Obesity Diabetes Alcohol Tobacco Oral contraceptive

Airborne Fungal Spores of Subalpine Zone of the Karkonosze and Izerskie Mountains(Poland)

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Journal of Mountain Science 2013年第6期10卷 940-952页

作者： wojciech PUSZ Wodzimierz KITA Andrzej DANCEWICZ Ryszard WEBER Department of Plant Protection Wroclaw University of Environmental and Life Sciences pl. Institute of Meteorology and Water Management-National Research Institute Institute of Soil Science and Plant Cultivation–National Research Institute

The incidence of the airborne fungal spores was determined in the air of subalpine zone of the Karkonosze Mountains and of the Izerskie Mountains in the borderland between Poland and the Czech Republic. The experiment was conducted in2011 and 2012 at three to four week intervals from May to October. Air samples were taken from three locations in the Karkonosze Mts. and one from the Izerskie Mts. To examine the air, the Air Ideal 3P sampler and acidified PDA medium were used. The results show that Cladosporium cladosporioides was the most abundant spore type in all the sampling locations(up to 30%), followed by Alternaria alternata(16%–20%), Fusarium(up to 10%) and Sclerotinia sclerotiorium(up to 6%). The lower spore counts were recorded in May samples, compared to the other months. In this case the snow cover, that was still present in the area at the beginning of May,may be the reason for the lower, compared to June,July and August samplings, CFU(Colony Forming Unit) counts in that month.. The influx of air masses from SE, S and SW sectors in the area under study may affect dissemination of the plant-pathogenic fungi from the Czech Republic and from the South of Europe in general.

关键词： Fungi Bioaerosol High mountainsaeromycology Pathogenic fungal spores Poland

Influence of the fly ash fraction after grinding process on the hydrothermal synthesis efficiency of Na-A,Na-P1,Na-X and sodalite zeolite types

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International Journal of Coal Science & Technology 2021年第2期8卷 291-311页

作者： Piotr Kunecki Rafal Panek Magdalena Wdowin Tomasz Bień wojciech Franus Mineral and Energy Economy Research Institute Polish Academy of SciencesWybickiego 7a31-261 KrakówPoland Lublin University of Technology Nadbystrzycka 4020-618 LublinPoland BIKO-SERWIS sp.z o.o.spóoka komandytowa Zakladowa 1326-052 NowinyPoland

The fly ashes(Class F and C)have been successfully used as the main substrates in the hydrothermal syntheses of Na-A,Na-P1,Na-X and sodalite *** ashes and their derivatives after milling with magnetic field grinder were *** paper investigates the effect of fly ash fraction size on the syntheses efficiency and physicochemical properties of the obtained *** starting material and obtained zeolites were subjected to physicochemical characteristics using X-ray diffraction,X-ray fluorescence,particle size analysis,and scanning electron microscopy *** paper showed a significant effect of the used fly ash fractions on the quantity,purity,quality and level of crystallinity of the zeolites phase *** application of the grinding process prior to the syntheses of zeolites,with a relatively small financial outlay,significantly increases their application *** zeolites are a promising material in the context of their use,inter alia,in environmental protection.

关键词： Grinding degree Magnetic field grinder Fly ash Synthetic zeolites Hydrothermal synthesis

Numerical simulation of a dense solid particle flow inside a cyclone separator using the hybrid Euler-Lagrange approach

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Particuology 2017年第2期15卷 170-180页

作者： Pawel Kozolub Adam Klimanek Ryszard A. Bialecki wojciech P. Adamczyk Institute of Thermal Technology Silesian University of Technology Konarskiego 22 Gliwice Poland AMEC Foster Wheeler Energia Polska Staszica 31 Sosnowiec Poland

This paper presents a numerical simulation of the flow inside a cyclone separator at high particle loads. The gas and gas–particle flows were analyzed using a commercial computational fluid dynamics code. The turbulence effects inside the separator were modeled using the Reynolds stress model. The two phase gas–solid particles flow was modeled using a hybrid Euler–Lagrange approach, which accounts for the four-way coupling between phases. The simulations were performed for three inlet velocities of the gaseous phase and several cyclone mass particle loadings. Moreover, the influences of several submodel parameters on the calculated results were investigated. The obtained results were compared against experimental data collected at the in-house experimental rig. The cyclone pressure drop evaluated numerically underpredicts the measured values. The possible reason of this discrepancies was disused.

关键词： Cyclone separator Two-phase flow Solid particle transport Computational fluid dynamics Hybrid Euler-Lagrange

Improved methodological concepts for processing liquid Mg at high temperature

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Journal of Magnesium and Alloys 2021年第1期9卷 183-191页

作者： Artur Kudyba Natalia Sobczak wojciech Polkowski Grzegorz Bruzda Adelajda Polkowska Donatella Giuranno Lukasiewicz Research Network-Krakow Institute of Technology Zakopianska 73 Str.30-418 KrakowPoland Institute of Metallurgy and Materials Science Polish Academy of Science25 Reymonta St.30-059 KrakówPoland National Research Council of Italy Institute of Condensed Matter Chemistry and Technologies for EnergyVia De Marini 616149GenovaItaly

In this paper,new improvements of methodological concepts upon examining wettability of high vapor pressure liquid metal systems(***-based alloys)in contact with refractory materials,are presented and *** this regard,high-temperature experiments on molten magnesium(Mg)in contact with graphite as a refractory substrate,were performed by utilizing a newly developed testing device and by applying a suitable experimental *** wetting experiments were carried out by the sessile drop method and under identical testing conditions(700℃/10 min under a protective gas atmosphere).Two different procedures were applied:the classical contact heating(CH)or a newly introduced capillary purification(CP)*** contact angle behaviors observed under the same conditions were strongly influenced by the applied ***,in the case of using the CH procedure,a presence of native surface oxide layer on the metal surface hinders the observations of melting process,making not possible to experimentally determine the wetting kinetics curveθ=f(t).Contrarily,during the wetting test performed on the Mg/graphite couple by applying the CP procedure,the native surface oxide layer was mechanically removed during the squeezing of the molten Mg through the hole of a ***,an oxide-free squeezed Mg-drop with regular and spherical shape was successfully obtained and dispensed on the graphite ***,the reliable contact angle value aroundθ=150°for the Mg/graphite system,was measured within the wetting test.

关键词： Mg-alloys Magnesium matrix composites Sessile drop Capillary purification procedure Wettability Contact angle

Photoluminescence and energy transfer in transparent glass-ceramics based on GdF3:RE3+（RE=Tb,Eu）nanocrystals

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Journal of Rare Earths 2019年第11期37卷 1137-1144页

作者： Natalia Pawlik Barbara Szpikowska-Sroka Ewa Pietrasik Tomasz Goryczka wojciech A.Pisarski Institute of Chemistry University of Silesia9 Szkolna StreetKatowice 40-007Poland Institute of Materials Science University of Silesia75 Putku Piechoty 1A StreetChorzow 41-500Poland

In the present work,the transparent oxyfluoride glass-ceramic samples containing GdF3:RE^3+(RE=Tb,Eu)nanocrystals(nGCs)were fabricated via controlled heat-treatment of precursor xerogels prepared using a sol-gel *** formation of GdF3 nanocrystalline phase from gadolinium(III)trifluoroacetate was verified based on XRD *** average crystal sizes calculated from Scherrer formula were estimated to^10 nm as well as^6 nm for Tb^3+-and Eu^3+-doped samples,*** optical behavior of prepared sol-gel samples was evaluated based on photoluminescence excitation(PLE)and emission spectra(PL)as well as luminescence decay *** samples exhibit the 5D4→7FJ(J=6-3,Tb3+)and the 5D0→7FJ(J=0-4,Eu3+)emission bands recorded within the visible spectral area under excitation at near-UV(393 nm(Eu^3+),351,369,378 nm(Tb^3+))as well as middle-UV illumination(273 nm(Gd3+)).Additionally,based on recorded decay curves,the luminescence lifetimes(τm)for the 5D4(Tb^3+)and the 5D0(Eu3+)excited states were also *** general,recorded luminescence spectra and double-exponential character of decay curves for nGCs indicate a successful migration of Tb^3+and Eu^3+dopant ions from amorphous silicate framework to lowphonon energy GdF3 nanocrystal phase.

关键词： Sol-gel method GdF3 nanocrystals Terbium Europium Rare earths